This relates generally to electronic devices, and more particularly, to electronic devices having plasmonic light sensors.
Plasmonic effects are quantum surface field effects in which an evanescent wave of electron density oscillations, also called plasmons, is generated on or near a surface of a metal or meta-material in response to incident photons. In structures designed to exhibit plasmonic effects, incoming photons incident on the plasmonic structure generate plasmons associated with high intensity electromagnetic fields within nano-scale distances from the surface of the structure. These high intensity electromagnetic fields couple to the incoming photons and can slow the photons down and change their course of near the plasmonic surface. These plasmonic effects have been demonstrated in structured metal coatings on lenses and on metal wires and have been demonstrated to guide light along structures significantly smaller than a single wavelength of light.
Conventional electronic devices use image sensors formed in a silicon substrate to capture light using image pixels formed in the silicon substrate. Conventional image pixels include photodiodes, formed in the substrate, that capture the light and convert the light into electrical charge. In a typical configuration, image pixels include microlenses and color filter elements formed in the silicon substrate that focus and filter incoming light onto the photodiodes. Conventional image pixels are unable to efficiently detect light having wavelengths larger than the image pixel size.
It would therefore be desirable to be able to provide improved electronic devices with plasmonic light sensors.